Monofins for various aquatic functions, ranging from cosmetic costumes to swimming aids, have been common in aquatic industries for years. Conventional monofins consist of a single fin attached to the user, and usually to the user's feet or legs. When attached to a user, a monofin can increase the propulsion force generated by a user while swimming by increasing the surface area of their kick cycle and by simulating the motions of a dolphin.
However, in aquatic activities where such equipment may not always be used, such as competitive swimming, monofins can actually be harmful to a swimmer's technique, since some monofins increase the efficiency of the user's kick cycle only by increasing the surface area of the user's effective kick. Training in this way fails to address and may even hamper proper kicking technique. Furthermore, many monofins and similar devices known in the art are only designed to function on or near the surface of a body of water. Currently, the aquatic aids and devices industry generally lacks a device capable of training for technique purposes, especially when the user is submerged under water.
When a swimmer is fully submerged underwater, the undulation of the swimmer's kick can be described in two phases. The first phase, termed the propulsive phase, is typified by the legs moving forward from behind the swimmer's prostrate horizontal midline. The second phase is termed the recovery phase This phase of motion is typified by the swimmer's legs returning from the front of the swimmer's midline to the back of the swimmer and the origin of the propulsive phase. While the recovery phase is substantially less powerful that the propulsive phase, maximizing the efficiency of both phases can be crucial to maximizing the speeds of competitive swimmers. Both phases are vital for the underwater undulation of a swimmer. An example of when this technique is pivotal to maximizing a swimmers efficiency is when the swimmer changes directions at a wall, an event known as a flip turn.
While it is substantially easier to achieve efficient power in the propulsive phase, the recovery phase can often be more difficult from a training perspective. The power from the recovery phase can be greatly improved when the swimmer's knees and ankle are straight. Previously known devices encourage and often require the user's ankles to bend and lose power, which consequently inhibits most effective swimming techniques and instead encourages inefficient techniques for unaided swimming.
A common problem for many swimmers, even those who are highly advanced, is a lack of a bilateral underwater kick. After kicking forward from behind the body, many swimmers do not extend the kick beyond the midline of the body. This bilateral motion is neglected in the use of conventional monofins, but is essential for competitive technique training. The foregoing disclosure details the first ever device that trains users to achieve this bilateral undulation of the legs while kicking in order to stimulate muscular development in both the power and return cycle of the kick, as well as train users to kick bilaterally. By feeling the undulating movement of the weight on the flexible, elongated member, the swimmer has to undulate fully in equal degrees to the front and back of the midline.